You mean 5 times the minimum of 1.5 km for special VFR?
Special VFR only applies within a Control Zone and is subject to ATC clearance.
Anyway, minimum visibility is 5 km below 10000 feet. If they were reporting 5 statute miles, which is 8 km, it's 1.6 times the minimum. BTW, 8 km is the minimum above 10000 feet.
Nope. I mean 5x the legal minimum of 1.5km flying in class G, in the UK and under 140kt.